Archive image from page 415 of The descent of man, and. The descent of man, and selection in relation to sex descentofmansele1874darw Year: 1874 402 THE DESCENT OF MAN. able to ascertain, is the general rule with lizards of all kinds. The male alone of the Cyrfodacfyles ruhidus of the Anda- man Islands possesses pre-anal pores; and these pores, judg- ing from analogy probably serve to emit an odor. The sexes often differ greatly in various external charac- ters. The male of the above-mentioned Anolis is furnished with a crest which runs along the back and tail, and can be erected at pleasure;
Archive image from page 415 of The descent of man, and. The descent of man, and selection in relation to sex descentofmansele1874darw Year: 1874 402 THE DESCENT OF MAN. able to ascertain, is the general rule with lizards of all kinds. The male alone of the Cyrfodacfyles ruhidus of the Anda- man Islands possesses pre-anal pores; and these pores, judg- ing from analogy probably serve to emit an odor. The sexes often differ greatly in various external charac- ters. The male of the above-mentioned Anolis is furnished with a crest which runs along the back and tail, and can be erected at pleasure; but of this crest the female does not exhibit a trace. In the Indian Cophotis ceylamca the female has a dorsal crest, though much less developed than in the male; and so it is, as Dr. Giinther informs me, with the females of many Iguanas, Chameleons and other lizards. In some species, however, the crest is equally developed in both sexes, as in the Iguana tuberculata. In the genus Sitana, the males alone are furnished with a large throat- pouch (tig. 33), which can be folded up like a fan, and is Fiff. 33. Sitana minor. Male with colored blue, black and red; tlrA-'xoixT but these splendid colors are exhibited only during the pair- ing-season. The female does not possess even a rudi- ment of this appendage. In the Anolis cristatellus accord- ing to Mr. Auster. the throat pouch, which is bright red marbled with yellow, is present in the female, though in a rudimental condition. Again, in certain other lizards, both sexes are equally well provided with throat pouches. Here we see with species belonging to the same group, as in so many previous cases, the same character either con- fined to the males or more largely developed in them than in the females, or again equally developed in. both sexes. The little lizards of the genus Draco, which glide through the air on their rib-supported parachutes, and which in the beauty of their colors baffle description are furnished with skinny
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